Irrigation and Conservation – Watering without wasting

Our approach to using water to irrigate lawns should be that of conservation. The supply is not endless — in fact, only one percent of the earth’s water is available for human consumption and use. The objective is to supplement only what the lawn requires and use this precious resource wisely.

How well soil absorbs water is a key factor in determining a lawn’s “personality” regarding length of time and day interval for irrigation. Factors affecting absorption are:

Soil type:

Clay soils absorb water more slowly than sandy soils.

Organic matter:

The amount in the soil helps balance air space and moisture retention.

Grade/slope:

Obviously, runoff occurs more quickly the steeper the slope.

Exposure to sun and wind:

Formulate a plan according to your environment, observing the lawn and how it responds after a rain and making allowances for unique situations.

What criteria indicate when a lawn needs to be watered? The simplest method is to walk across the lawn and look back at the path just taken. Visible foot impressions indicate the early stages of moisture stress, and irrigation will be needed if adequate rainfall does not occur.

Another means is to use a trowel or screwdriver to loosen the soil surface then judge the moisture level of the soil by touch. Remember, the soil surface dries out quickly, while the top inch of soil may be plenty moist to sustain the turf.

The goal is to stretch out the time between watering for as long as possible. This will encourage deep-root growth from four to six inches and is advantageous in case of prolonged drought or water restrictions. The recovery of a lawn from a dry period is much better if the turf has a deep, well-established root system. Other benefits to the lawn by infrequent watering include minimizing disease problems and unnecessary water loss due to evaporation.

Apply one to one-and-a-half inches deep of water every seven to ten days during dry periods. In July and August, it may be necessary to water on a five-to-seven-day interval.

Efficient use of water means irrigating to the point of runoff, stopping until the water has been absorbed, and then resuming. To accomplish this, set a rain gauge or a tuna can on the lawn. Start the irrigation system, whether it is an automatic (underground system) or manual (hose and sprinkler). Note when excessive water runoff starts to occur, stop the water.

Let’s say you watered for 10 minutes and the gauge measures .25 inches of water. To minimize runoff with a manual system, water each area for 10 minutes, and then move the sprinkler to another area to allow water to soak into the soil. Alternate sites until each area has been watered 40 total minutes or one inch.

Automatic systems, given the above scenario, should be set for 10 minutes per turf zone and programmed for four consecutive start times on the same day. This will give 40 minutes or one inch of water to the lawn. With five turf zones, that would be 50 total minutes for one cycle of irrigation to all turf zones. The first start time might be 4 a.m., the second at 5 a.m. The third and fourth cycles will continue the progression established between the first and second start times.

Consideration and time should be taken to ensure that your irrigation process is wasting as little water as possible. Especially with automatic systems, this means testing periodically to make sure there are no missing heads shooting up into the air or misaligned heads spraying into the street instead of the lawn. Repair leaks and make adjustments in a timely manner to minimize unnecessary water loss. Make sure that spray patterns are not being interfered with by a tree, shrub or foliage of some type.

Be diligent stewards of our water. Take the time to manage your water use. Don’t take the easy way out and water daily for your convenience. This precious resource does not have an endless supply!

Question:

Jimmie, I am considering a new tree purchase and I am not educated enough to know the difference or quality difference between the selection I was shown at several nurseries. They apparently have different ways of selling the same type of tree. For instance, I was looking to purchase a Live Oak tree and I noticed some in containers, some in big piles of what looked like sawdust. The ones in containers were priced much higher, even though the ones in sawdust looked just as good? Is there a big difference? Thanks by the way for taking the time to help people like me out!

Scott L. in Prosper

Answer: Hi Scott, Great Question!!!

Nurseries sell trees in three forms: bare root, balled-and-burlapped and containerized. Bare root trees, as the name implies, lack soil or growing media on their roots. Therefore, it is imperative never to let the roots dry. The prudent planter should soak the roots in water or cover them with wet peat moss and store them in a cool place until planting time. Balled-and-Burlapped trees, on the other hand, retain their native soil. Although losing 90 percent or more of their root system during the digging process, B and B trees generally have a higher survival rate than transplanted bare root stock; yet, if the root ball is not kept intact during transplanting, survival is reduced considerably. Containerized plants are currently very popular. However, containerized plants frequently suffer from poor root structure. While often not apparent at planting time, kinked or encircling roots will cause future health problems for the transplant. During the transplanting process, these deformities must be gently straightened or cut!

When choosing the right tree for your home, remember the following Five S’s: Specific, Site, Space, Structure, and Standards. Specific refers to the purpose of your new tree, i.e., shade, privacy, color, etc. Always choose a species that corresponds to your landscape need. Likewise, site refers to the matching of plant biological requirements to the physical conditions of the site. For example, plants which prefer acidic soil must be planted in acidic soil and vice versa. Thirdly, space describes the need for adequate room above (both vertically and horizontally) and below ground for future growth. The fifth parameter of selection is structure. This refers to an individual specimen’s physical attributes. Is the trunk straight and well tapered? Are the branches well distributed along the entire trunk and are they smaller than the main trunk? Do 50 percent or more of the branches originate in the lower two-thirds of the trunk? Are there any significant wounds on the branches or trunk? The final selection parameter, standards, refers to the proper height and root ball proportions as defined in the American Standards for Nursery Stock. Of the standards mentioned within the manual, the most important one is the standard concerning root ball size. With the exception of very large diameter root balls, minimum root ball diameter should equal or exceed a ratio of 12 inches for each inch trunk caliper. Above all else, examine carefully before you buy and buy for quality!!!

Jimmie is a Prosper resident and the owner of Absolutely Bushed Landscaping Company, an award winning, family and veteran owned and operated business created in 1980 to provide the highest quality custom Outdoor Renovation available to homeowners in the Dallas Ft. Worth area.